Dave Saxton wrote:The Rodney 16" had essentially the same belt penetration as the Iowa 16"/50 and the German 15"/52 at 20,000 yards....On the other side of the ledger the 16" guns can not defeat the Scharnhorst's scarp triangle belt protection system.
FWIW, doing a little crunching with Naab yields these figures:
Belt / Deck Iowa SoDak Nelson Bismarck
15k yards 22.0/3.3 19.4/3.4 19.3/2.8 19.6/2.5
20k yards 19.1/3.9 16.8/4.0 16.2/3.3 16.5/3.1
25k yards 16.9/4.5 14.7/5.0 13.9/4.1 14.2/3.6
Numbers are derived from specifying complete penetrations into 12" worth of German improved thick-plate KC n/A backed by 1" of mild steel for vertical plating, and 5" of Wotan Weich for horizontal plating. For the US figures, I used the 16" Mk8 Mod 6-8 APC, with an MV of 2500fps and 2300fps for Iowa and SoDak respectively. With the above, the US 16/L45 appears fairly comparable with the weapons aboard Bismarck and Nelson, with Iowa's 16/L50 representing an incremental improvement in vertical armor penetration.
In terms of "tearing ships apart"...certainly all of the above will do that at any realistic battle range. As resilient as the German scarp/belt system is, Scharnhorst as a whole is quite vulnerable to these weapons.